Geoscience Reference
In-Depth Information
Seismostratigraphic Analysis and Glacial
History of the Weddell Sea Region,
Antarctica
Xiaoxia Huang and Karsten Gohl
Abstract The Weddell Sea basin is of particular signi
cance for understanding
climate processes,
including the generation of ocean water masses and their
in
uence on ocean circulation as well as the dynamics of the Antarctic ice sheets.
The sedimentary record, preserved below the basin
fl
floor, serves as an archive of the
pre-glacial to glacial development of these processes, which were accompanied by
tectonic processes in its early glacial phase. Three multichannel seismic re
fl
ection
transects, in total nearly 5,000 km long, are used to interpret horizons and de
fl
ne a
seismostratigraphic model for the basin. We expand this initial stratigraphy model
to the greater Weddell Sea region through a network of more than 50 additional
seismic lines. Information from few boreholes are used to constrain sediment ages
in this stratigraphy, supported by magnetic anomalies indicating decreasing oceanic
basement ages from southeast to northwest. Using these constraints, we calculate
grids to depict the depths, thicknesses and sedimentation rates of pre-glacial (145
-
34 Ma), transitional (34
15 Ma) and full-glacial (15 Ma to present) units. Sedi-
mentation thicknesses and sedimentation rates were calculated at the 12 selected
points in the entire basin to give a brief overview of the deposition history, which
will contribute to the understanding of the Antarctic ice sheet development and
dynamics from the greenhouse to icehouse world in the Cenozoic.
-
1 Introduction
The breakup of Gondwana and the subsequent opening of Southern Ocean basins
and gateways coincided with changes to global ocean circulation and climatic
conditions. Changes in the geometry and geography of landmasses and ocean basins
lead to
first-order ocean current distribution and marine sedimentation patterns
Search WWH ::
Custom Search